Helga Noice, a psychologist from Elmhurst College in Illinois, and Tony Noice, an actor, who together discovered this effect, found that non-thesps can benefit by adopting a similar technique. Students who paired their words with previously learned actions could reproduce 38 per cent of them after just 5 minutes, whereas rote learners only managed 14 per cent. The Noices believe that having two mental representations gives you a better shot at remembering what you are supposed to say.

Strategy is important in everyday life too, says Barry Gordon from Johns Hopkins University in Baltimore, Maryland. Simple things like always putting your car keys in the same place, writing things down to get them off your mind, or just deciding to pay attention, can make a big difference to how much information you retain. And if names are your downfall, try making some mental associations. Just remember to keep the derogatory ones to yourself.

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SKIMPING on sleep does awful things to your brain. Planning, problem-solving, learning, concentration,working memory and alertness all take a hit. IQ scores tumble. "If you have been awake for 21 hours straight, your abilities are equivalent to someone who is legally drunk," says Sean Drummond from the University of California, San Diego. And you don't need to pull an all-nighter to suffer the effects: two or three late nights and early mornings on the trot have the same effect.

Luckily, it's reversible - and more. If you let someone who isn't sleep-deprived have an extra hour or two of shut-eye, they perform much better than normal on tasks requiring sustained attention, such taking an exam. And being able to concentrate harder has knock-on benefits for overall mental performance. "Attention is the base of a mental pyramid," says Drummond. "If you boost that, you can't help boosting everything above it."

These are not the only benefits of a decent night's sleep. Sleep is when your brain processes new memories, practises and hones new skills - and even solves problems. Say you're trying to master a new video game. Instead of grinding away into the small hours, you would be better off playing for a couple of hours, then going to bed. While you are asleep your brain will reactivate the circuits it was using as you learned the game, rehearse them, and then shunt the new memories into long-term storage. When you wake up, hey presto! You will be a better player. The same applies to other skills such as playing the piano, driving a car and, some researchers claim, memorising facts and figures. Even taking a nap after training can help, says Carlyle Smith of Trent University in Peterborough, Ontario.

There is also some evidence that sleep can help produce moments of problem-solving insight. The famous story about the Russian chemist Dmitri Mendeleev suddenly "getting" the periodic table in a dream after a day spent struggling with the problem is probably true. It seems that sleep somehow allows the brain to juggle new memories to produce flashes of creative insight. So if you want to have a eureka moment, stop racking your brains and get your head down.

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IT'S a dream come true for those who hate studying. Simply walking sedately for half an hour three times a week can improve abilities such as learning, concentration and abstract reasoning by 15 per cent. The effects are particularly noticeable in older people. Senior citizens who walk regularly perform better on memory tests than their sedentary peers. What's more, over several years their scores on a variety of cognitive tests show far less decline than those of non-walkers. Every extra mile a week has measurable benefits.

It's not only oldies who benefit, however. Angela Balding from the University of Exeter, UK, has found that schoolchildren who exercise three or four times a week get higher than average exam grades at age 10 or 11. The effect is strongest in boys, and while Balding admits that the link may not be causal, she suggests that aerobic exercise may boost mental powers by getting extra oxygen to your energy-guzzling brain.

There's another reason why your brain loves physical exercise: it promotes the growth of new brain cells. Until recently, received wisdom had it that we are born with a full complement of neurons and produce no new ones during our lifetime. Fred Gage from the Salk Institute in La Jolla, California, busted that myth in 2000 when he showed that even adults can grow new brain cells. He also found that exercise is one of the best ways to achieve this.

In mice, at least, the brain-building effects of exercise are strongest in the hippocampus, which is involved with learning and memory. This also happens to be the brain region that is damaged by elevated levels of the stress hormone cortisol. So if you are feeling frazzled, do your brain a favour and go for a run.

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